Display dolly

ABSTRACT

A display dolly is formed from an upper shell and a lower shell that are thermoformed from first and second sheets of material. The upper and lower shells are formed and attached to each other using a twin-sheet thermoforming process that provides a hollow internal cavity between the shells. The upper shell provides an upper surface to support a display. The lower shell includes wheel mount interfaces to receive wheels such that the display can be moved to a desired location. In one example, the upper shell includes a first plurality of corrugations and the lower shell includes a second plurality of corrugations that extend in a different direction than that of the first plurality of corrugations.

BACKGROUND OF THE INVENTION

Display dollies can be shipped from a product manufacturer with the display already installed on the dolly. The dolly is held fixed in place on a pallet. Straps are used to secure the display and dolly to the pallet. The pallet, dolly, and display are then shipped as a single unit to a store. Once at the store, the straps are cut and a lifting device lifts the dolly and the display from the pallet. The dolly is then placed on a floor and the display is wheeled on the dolly to the desired location.

A typical display dolly includes a support platform with wheels. The platform is formed from injection molded plastic and then the wheels are attached. The injection molding process is expensive and is not easily adaptable to providing different shapes for the platform.

SUMMARY OF THE INVENTION

The present invention provides a dolly that movably supports a display.

An example display dolly includes an upper shell and a lower shell that are formed by thermoforming first and second sheets of material. The upper and lower shells are formed and attached to each other using a twin-sheet thermoforming process that provides a hollow interior cavity between the shells. The upper shell provides an upper surface to support the display. The lower shell includes wheel mount interfaces that receive wheels to move the display dolly along with the display to a desired location.

In one example, the upper shell includes a first plurality of corrugations or trenches and the lower shell includes a second plurality of corrugations or trenches. The first and second pluralities of corrugations are orientated to extend in different directions from each other.

In one example, the wheel mount interfaces are formed as cup-shaped recesses within the lower shell. For each wheel mount interface in the lower shell, a corresponding cup shaped recess is formed within the upper shell. Each cup-shaped recess includes an opening formed in a bottom of the recess to receive a fastener. The cup-shaped recesses of the upper and lower shells are placed in an overlapping relationship and fasteners are inserted through the openings. The fasteners secure the wheels to the display dolly and also further secure the upper and lower shells together.

These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a pallet, display dolly, and display.

FIG. 2 is a perspective view of another example of a display dolly on a pallet.

FIG. 3 comprises an exploded view showing the display dolly of FIG. 1 being removed from the pallet.

FIG. 4 is a perspective top view of the display dolly of FIG. 1.

FIG. 5 is a perspective bottom view of the display dolly of FIG. 4.

FIG. 6 is an exploded view of the display dolly of FIG. 4 showing upper and lower shells.

FIG. 7 is a top view of the upper shell.

FIG. 8 is a bottom view of the lower shell without wheels.

FIG. 9 is a bottom view of the lower shell with the wheels installed.

FIG. 10 is an end view of the display dolly of FIG. 4 with the display.

FIG. 11 is an end view opposite of that of FIG. 10.

FIG. 12 is a sectioned view of a display dolly showing one example of a wheel mount interface.

FIG. 13 is a sectioned view of a display dolly showing another example of a wheel mount interface.

FIG. 14 is a sectioned view of a display dolly showing one example of a display mount interface.

FIG. 15 is a top view of a display dolly showing one example of a raised support surface for the display.

FIG. 16 is a perspective view of a platform incorporating the subject invention.

FIG. 17 is a bottom view of the platform of FIG. 16.

FIG. 18 is a schematic representation of a twin-sheet thermoforming process used to form the display dolly and platform.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 shows a pallet 10 with a wheel retention feature 12 that receives wheels 14 of a dolly 16. The dolly 16 provides a support surface 18 to support a display 20. In the example shown, the wheel retention feature 12 comprises two pairs of upwardly extending rails 22, with each pair of rails 22 being separated by a gap 24 that receives the wheels 14. The rails 22 help prevent movement of the dolly 16 relative to the pallet 10 during shipping.

Straps (not shown) are also used to secure the display 20 and the dolly 16 to the pallet 10. In the example shown in FIG. 2, a strap retention feature 26 is formed within the dolly 16 at a location over the wheels 14. The strap retention feature 26 in this example comprises a pair of corrugations or grooves 28 that extend across a width of the dolly 16 to receive the straps. Walls 30 of the groove 28 prevent the straps from moving in an axial direction corresponding to a side length of the dolly 16.

To remove the dolly 16 from the pallet 10, the straps are cut and a lifting device, such as a forklift for example, is used to lift the dolly 16 and display 20 (FIG. 1) from the pallet 10 as shown in FIG. 3. As shown, blocks 32 are fixed to the pallet 10 to facilitate support of the dolly 16 and locating of the wheels 14 relative to the pallet 10. Once the dolly 16 has been removed from the pallet 10, the dolly 16 can be placed on the wheels 14 as shown in FIG. 4 such that the dolly 16 with the associated display 20 can be moved to a desired location. FIG. 4 shows that the dolly 16 is defined by a width W, a length L, and a height H.

As shown in FIG. 5, the wheels 14 are caster wheels that allow the dolly 16 to be easily moved in multiple directions. Other types of wheels could also be used.

The dolly 16 is comprised of an upper shell 40 and a lower shell 42 as shown in FIG. 6. The upper shell 40 comprises a first thermoformed sheet and the lower shell 42 comprises a second thermoformed sheet. The shells are formed and attached to each other using a twin-sheet thermoforming process. Thermoforming the shells 40, 42 significantly reduces cost compared to prior injected molded dollies. Further, shapes of the shells can be more easily changed when a thermoforming process is used as opposed to injection molding. In the twin-sheet thermoforming process, first and second heated plastic sheets of material are drawn against upper and lower female molds. The molds are then brought together and the heated sheets of material are compressed at joining areas defined by the molds. When the sheets cool, the desired hollow/double-walled shape is formed.

As shown in FIG. 6, the upper shell 40 includes a first plurality of discretely spaced grooves, trenches, or corrugations 44. The corrugations 44 are linear formations that are orientated to extend in an axial direction across the width W of the dolly 16. The corrugations 44 are spaced apart from each other in an axial direction across the length L of the dolly 16. The corrugations 44 are separated from each other by generally flat areas 46 that form the support surface 18 to support the display 20 (FIG. 1).

Also as shown in FIG. 6, the lower shell 42 includes a second plurality of discretely spaced grooves, trenches, or corrugations 48. The corrugations 48 are linear formations that are orientated to extend in an axial direction across the width L of the dolly 16. The corrugations 48 are spaced apart from each other in an axial direction across the length W of the dolly 16. The corrugations 48 are separated from each other by generally flat areas 50. The length of the corrugations 44, 48 can be the same or varied as needed to adjust for purposes of strength, shape, or size constraints that could vary between different types of displays.

Thus, the corrugations 44 in the upper shell 40 extend in one direction and the corrugations 48 in the lower shell 42 extend in a different direction. In one example, the corrugations 44 in the upper shell 40 are perpendicular to the corrugations 48 in the lower shell 42. This orientation of the corrugations 44, 48 provides increased structural rigidity for the dolly 16.

Wheel mount interfaces 52 are formed within the lower shell 42 as shown in FIG. 6. Each wheel mount interface 52 receives one wheel 14. Fasteners 54 are used to secure the wheels 14 to the dolly 16.

As shown in FIG. 7, the upper shell 40 is formed as a box-shape with a first pair of opposing side edges 56 that are connected to each other by a second pair of opposing side edges 58. The first pair of opposing side edges 56 defines the width W and the second pair of opposing side edges 58 defines the length L. Corrugations 60 are formed within the side edges 56, 58. Also in addition to the corrugations 44 and corrugations 60, additional pocket recesses 62 can be formed within the upper shell 40. The corrugations 60 and pocket recesses 62 reduce the weight of the dolly 16. Further, while corrugations 60 are shown as being formed on each of the edges 56, 58, corrugations could be utilized on only some or none of the edges.

The upper shell 40 also includes upper wheel mount interfaces 64 that correspond to lower wheel mount interfaces 66 on the lower shell 42 as shown in FIG. 8. The lower shell 42 is formed as a box-shape with a first pair of opposing side edges 68 that are connected to each other by a second pair of opposing side edges 70. Corrugations 72 are formed within at least one of the side edges. While corrugations 72 are shown as being formed on only one set of the opposing side edges, corrugations could be utilized on all, some, or none of the edges.

As shown in FIG. 8, the lower wheel mount interfaces 66 each include a cross-shaped deformation 74. In the example show, the cross-shaped deformation comprises a pair of groves that intersect each other in a perpendicular relationship. This cross-shaped deformation 74 provides additional support for the wheels 14 as shown in FIG. 9.

FIGS. 10 and 11 show end views of the dolly 16. FIG. 10 shows the side edges 58 that define the length L of the dolly 16 and FIG. 11 shows the side edges 56 that define the width W of the dolly 16. FIG. 10 also shows the display 20 placed on top of the dolly 16.

FIG. 12 shows a cross-sectional view of the dolly 16 at the upper 64 and lower 66 wheel mount interfaces. Each lower wheel mount interface 66 comprises a cup-shaped recess having a bottom portion 76 having an opening 78 to receive the fastener 54 that is used to secure the wheel 14 to the dolly 16. A wall portion 80 transitions upwardly from the bottom portion 76 to open to an upper surface 82 of the lower shell 42. A raised boss 84 extends upwardly from the bottom portion 76 and includes the opening 78. The bottom portion 76 is defined by a first diameter D1.

Each upper wheel mount interface 64 comprises a corresponding cup shaped recess that has a bottom portion 86 having an opening 88 to receive the fastener 54 that is used to secure the wheel 14 to the dolly 16. A wall portion 90 transitions upwardly from the bottom portion 86 to open to an upper surface 92 of the upper shell 40. A boss portion 94 extends downwardly from the bottom portion 86 and includes the opening 88. The bottom portion 86 is defined by a second diameter D2.

In the example shown in FIG. 12, the second diameter D2 is greater than the first diameter D1. The lower shell 42 includes a recessed area 96 that receives the bottom portion 86 of the upper wheel mount interface 64. The wall portion 80 of the lower wheel mount surface transitions into this recessed area 96. As such, when the cup-shaped recesses of the upper 64 and lower 66 wheel mount interfaces are positioned in an overlapping relationship, the bottom portion 86 of the upper wheel mount interface 64 abuts or rests on the surface of the recessed area 96. Also, when the upper 64 and lower 66 wheel mount interfaces are positioned in an overlapping relationship, the openings 78, 88 are aligned with each other to receive the fasteners 54.

Each fastener 54 is used to secure one wheel 14 to the dolly 16. The fasteners 54 also serve to further secure the upper 40 and lower 42 shells together. As discussed above, the upper 40 and lower 42 shells are initially attached together during the twin-sheet thermoforming process to define an interior cavity 100 between the upper 40 and lower 42 shells as shown in FIG. 12.

FIG. 13 shows another example of an upper 102 and lower 104 wheel mount interface. In this example, each lower wheel mount interface 104 comprises a cup-shaped recess having a bottom portion 106 having an opening 108 to receive the fastener 54 that is used to secure the wheel 14 to the dolly 16. A wall portion 110 transitions upwardly from the bottom portion 106 to open to an upper surface 112 of the lower shell 42. The bottom portion 106 is defined by a first diameter D1.

Each upper wheel mount interface 102 comprises a corresponding cup shaped recess that has a bottom portion 114 having an opening 116 to receive the fastener 54 that is used to secure the wheel 14 to the dolly 16. A wall portion 118 transitions upwardly from the bottom portion 114 to open to an upper surface 120 of the upper shell 40. The bottom portion 114 is defined by a second diameter D2. In the example shown in FIG. 13, the first diameter D1 is greater than the second diameter D2.

When the upper 102 and lower 104 wheel mount interfaces are positioned in an overlapping relationship, the bottom portion 114 of the upper wheel mount interface 102 abuts or rests against the bottom portion 106 of the lower wheel mount interface 104. Also, when the upper 102 and lower 104 wheel mount interfaces are positioned in an overlapping relationship, the openings 108, 116 are aligned with each other to receive the fasteners 54.

FIG. 13 also shows that the corrugations 48 in the lower shell 42 form corresponding protrusions 122 that extend downwardly from a lower surface 124 of the lower shell 42. Corrugations 44 in the upper shell 40 form corresponding protrusions 126 that extend downwardly from a lower surface 128 of the upper shell 40 as shown in FIG. 14. The protrusions 126 from the upper shell 40 are non-parallel relative to the protrusions 122 from the lower shell 42. Further, bottom surfaces of the protrusions 126 in the upper shell 40 are spaced apart from the upper surface of the lower shell 42 when the shells 40, 42 are attached to each other.

FIG. 14 is a sectional view taken at a display mount area 130. The upper shell 40 includes a first set of downwardly extending mount bosses 132 that face a second set of upwardly extending mount bosses 134 formed in the lower shell 42. Each downwardly extending mount boss 132 includes an opening 136 to receive a fastener (not shown) and each upwardly extending mount boss 134 includes an opening 138 to receive the fastener. The openings 136, 138 are aligned with each other once the upper 40 and lower 42 shells are secured together. Once aligned, fasteners are inserted into the openings 136, 138 to secure the display 20 (FIG. 1) to the dolly 16.

As shown in FIGS. 14 and 15, the upper shell 40 can also include raised corner areas 140 to provide additional support for the display 20.

The twin-sheet thermoforming process can also be used to form a support platform 200 as shown in FIGS. 16-17 that does not include wheels. The platform 200 includes an upper shell 202 and a lower shell 204 that are attached to each other during a twin-sheet thermoforming process to form an interior cavity as described above. The upper shell 202 includes a first plurality of grooves, trenches, or corrugations 206 that are spaced apart from each other by generally flat areas 208. Each corrugation 206 is linear in formation and extends in a first axial direction.

The lower shell 204 includes a second plurality of grooves, trenches, or corrugations 210 that are spaced apart from each other by generally flat areas 212 as shown in FIG. 17. Each corrugation 210 is linear in formation and extends in a second axial direction that is different than the first axial direction. In other words, corrugations in the upper shell 202 are non-parallel to corrugations formed in the lower shell 204. In the example shown, the first 206 and second 210 pluralities of corrugations are perpendicular to each other. Additional corrugations 214 could also be formed within side walls of the platform 200 similar to those discussed above.

FIG. 18 shows a schematic representation of the twin-sheet thermoforming process that is used to make the dolly 16 and the platform 200. A first mold 300 defines the upper shell with a first plurality of corrugations 302. A second mold 304 defines the lower shell with a second plurality of corrugations 306 (only one is shown) that extend in a different direction than the first plurality of corrugations 302. A vacuum source V draws a first heated sheet of plastic material 308 against the first mold 300 to form the upper shell. The vacuum source V draws a second heated sheet of plastic material 310 against the second mold 304 to form the lower shell. A press P then moves the heated sheets of plastic material 308, 310 toward each other, as indicated by arrows 312 such that the shells are compressed together at joining areas. As such, two sheets are thermally welded into a single part, i.e. a dolly or a platform, without having to use adhesives or fasteners.

Although a preferred embodiment of this invention has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope and content of this invention. 

1. A display dolly comprising: a first thermoformed sheet forming an upper shell, the upper shell providing a support surface for a display; and a second thermoformed sheet forming a lower shell that is secured to the upper shell to form an internal cavity between the upper and lower shells, and wherein the lower shell includes a plurality of wheel mount interfaces for connection to wheels to provide a movable display dolly.
 2. The display dolly of claim 1 wherein the upper shell includes a first plurality of corrugations that extend in a first direction and the lower shell includes a second plurality of corrugations that extend in a second direction different than the first direction.
 3. The display dolly of claim 2 wherein the first plurality of corrugations comprise a first set of discretely spaced linear corrugations that extend in a lateral direction and wherein the second plurality of corrugations comprise a second set of discretely spaced linear corrugations that extend in a longitudinal direction that is transverse to the lateral direction.
 4. The display dolly of claim 3 wherein the first set of discretely spaced linear corrugations is perpendicular to the second set of discretely spaced linear corrugations.
 5. The display dolly of claim 2 wherein the upper shell includes an upper surface and a lower surface, and wherein the first plurality of corrugations forms a series of discretely spaced linear recesses extending downwardly into the upper surface with a corresponding series of discretely spaced linear protrusions extending outwardly from the lower surface, and wherein a bottom surface of the protrusions is spaced apart from an upper surface of the lower shell.
 6. The display dolly of claim 5 wherein the second plurality of corrugations forms a series of discretely spaced linear recesses extending downwardly into the upper surface of the lower shell with a corresponding series of discretely spaced linear protrusions extending outwardly from a lower surface of the lower shell, and wherein the protrusions of the upper shell are non-parallel relative to the protrusions of the lower shell.
 7. The display dolly of claim 1 wherein each wheel mount interface comprises a cup-shaped recess formed within the lower shell and including corresponding cup-shaped recesses formed within the upper shell that overlap the cup-shaped recesses in the lower shell, and wherein the cup-shaped recesses in the upper and lower shells each include an opening to receive a fastener that secures a wheel to the display dolly.
 8. The display dolly of claim 7 wherein the cup-shaped recess in the lower shell includes a first bottom portion defined by a first diameter and wherein the corresponding cup-shaped recess in the upper shell includes a second bottom portion defined by a second diameter that is different than the first diameter.
 9. The display dolly of claim 8 wherein the second diameter is greater than the first diameter.
 10. The display dolly of claim 8 wherein the second diameter is less than the first diameter.
 11. The display dolly of claim 8 wherein the first bottom portion includes an upwardly extending boss that defines a first opening to receive the fastener and wherein the second bottom portion includes a downwardly extending boss that defines a second opening to receive the fastener.
 12. The display dolly of claim 8 wherein a lower surface of the first bottom portion includes a cross-shaped depression to provide additional wheel support.
 13. The display dolly of claim 1 wherein the upper shell is bounded by a first pair of opposing wall portions that are connected to each other by a second pair of opposing wall portions and wherein the lower shell is bounded by a third pair of opposing wall portions that are connected to each other by a fourth pair of opposing wall portions, and wherein at least one of the first, second, third, and fourth opposing wall portions include a plurality of corrugations.
 14. A portable display comprising: a pallet including a wheel retention area; a display dolly supported by the pallet, the display dolly including a plurality of wheels that are held within the wheel retention area; a display supported on the display dolly wherein the display dolly is selectively removable from the pallet such that the wheels can move the display to a desired location; and wherein the display dolly comprises: a first thermoformed sheet forming an upper shell, the upper shell providing a support surface for a display; and a second thermoformed sheet forming a lower shell that is secured to the upper shell to form an internal cavity between the upper and lower shells, and wherein the lower shell includes a plurality of wheel mount interfaces for connection to the wheels.
 15. The portable display of claim 14 wherein the upper shell includes a first plurality of corrugations that extend in a first direction and the lower shell includes a second plurality of corrugations that extend in a second direction different than the first direction.
 16. The portable display of claim 15 wherein the first and second directions are perpendicular to each other.
 17. The portable display of claim 14 wherein the upper and lower shells are secured together with fasteners installed at the wheel mount interfaces.
 18. The portable display of claim 17 wherein each wheel mount interface comprises a cup-shaped recess formed within the lower shell and including corresponding cup-shaped recesses formed within the upper shell that overlap the cup-shaped recesses in the lower shell, and wherein overlapping cup-shaped recesses in the upper and lower shells each include openings to receive one fastener that secures the wheel to the display dolly.
 19. A method of forming a display dolly comprising: thermoforming a first sheet to form an upper shell having a support surface for a display; thermoforming a second sheet to form a lower shell including forming a plurality of wheel mount interfaces for connection to wheels to provide a movable display dolly; and securing the upper and lower shells together to form an internal cavity between the upper and lower shells.
 20. The method of claim 19 including forming a first plurality of corrugations in the upper shell that extend in a first direction and forming a second plurality of corrugations in the lower shell that extend in a second direction different than the first direction.
 21. The method of claim 20 wherein the first and second directions are perpendicular to each other.
 22. The method of claim 19 including securing the upper and lower shells together by compressing joining areas of heated upper and lower shells together.
 23. The method of claim 22 including forming each wheel mount interface as a cup-shaped recess within the lower shell, forming corresponding cup-shaped recesses within the upper shell that overlap the cup-shaped recesses in the lower shell, forming openings in the cup-shaped recesses in both the upper and lower shells, aligning corresponding openings for overlapping cup-shaped recesses, and inserting one fastener into each pair of aligned openings to secure the wheel to the display dolly at the wheel mount interface and to further secure the upper and lower shells together.
 24. A method of forming a platform comprising: thermoforming a first sheet to form an upper shell having a first plurality of corrugations; thermoforming a second sheet to form a lower shell having a second plurality of corrugations that are non-parallel to the first plurality of corrugations; and securing the upper and lower shells together to form a platform having a hollow cavity between the upper and lower shells.
 25. The method of claim 24 including forming each corrugation of the first plurality of corrugations to extend in a first axial direction and forming each corrugation of the second plurality of corrugations to extend in a second axial direction that is transverse to the first axial direction.
 26. The method of claim 25 wherein the first and second axial directions are perpendicular to each other.
 27. The method of claim 24 including securing the upper and lower shells together during thermoforming by compressing joining areas of heated upper and lower shells together.
 28. A platform comprising: a first thermoformed sheet forming an upper shell having a first plurality of corrugations; and a second thermoformed sheet forming a lower shell having a second plurality of corrugations that are non-parallel to the first plurality of corrugations wherein the upper and lower shells are secured together to form a platform having a hollow cavity between the upper and lower shells.
 29. The platform of claim 28 wherein each corrugation of the first plurality of corrugations extends in a first axial direction and each corrugation of the second plurality of corrugations extends in a second axial direction that is transverse to the first axial direction.
 30. The platform of claim 29 wherein the first and second axial directions are perpendicular to each other. 